Domain-based Message Authentication, Reporting, and Conformance (DMARC) presents a host of hurdles for companies implementing it themselves. If you can navigate the first step of the enforcement process (parsing XML data from aggregate reports, translating IP addresses to sender names, and correctly categorizing malicious senders, approved senders, and shadow IT), which is no small feat, you can move on to the next step of the DMARC process—configuring Sender Policy Framework (SPF) and DomainKeys Identified Mail (DKIM) for each sender.
Unfortunately, many senders are behind the times when it comes to getting SPF and DKIM configurations right, and it’s up to your team to understand what is really necessary.
You would think that all you need to do is contact your vendor and ask them what SPF and DKIM information you need to add to your DNS and be done with it.
Unfortunately, it’s not always that easy.
Each email sender tends to handle email authentication differently, and some senders aren’t even familiar with the latest processes.
Two main scenarios could complicate your DMARC process when working with third-party senders:
DMARC and third-party sender challenges
1. The sender doesn’t understand the additional requirements that DMARC places on SPF and DKIM
Before DMARC came along, alignment (the return path and/or DKIM domain matching the From domain) was not a requirement. And even though DMARC is over six years old, it’s not as widespread as it should be. As a result, senders who have not kept up with the times may give you incorrect SPF or DKIM information.
There are a couple of ways this could happen: Their system does not support DMARC-compliant emails, or the person you are speaking to at your vendor does not have the most up-to-date information. In some cases, senior technical groups may be aware of DMARC’s requirements, but this may not have reached the frontline support teams.
There may also be cases where the sender has never had to send DMARC-compliant emails and does not know what is involved. While most vendors are now familiar with SPF, they might not have experience implementing it in combination with DMARC.
2. Out-of-date methods and configurations
The evolution of email authentication has made older standards like SenderID and DomainKey (which is different from DKIM) obsolete, but some vendors still direct you to configure them.
It’s a red flag if your senders mention these configurations in reference to DMARC. These standards do not impact DMARC, which means they are useless in getting your emails authenticated and delivered under a DMARC enforcement policy. While it’s not harmful to implement these standards, they don’t reflect the modern era of email authentication.
In some cases, vendors’ verification systems themselves may be out of date, which could lead you to believe you have a problem, then spend a lot of time dissecting it, only to determine there was no issue at all.
These issues seem minor but can quickly exhaust your resources and derail your DMARC progress.
How to solve third-party sender DMARC issues
Third-party senders can introduce significant challenges to your email authentication efforts, particularly when it comes to DMARC compliance. To limit the risk associated with these issues, you’ll need a subject-matter expert to guide the vendors on the following critical topics:
- DMARC Alignment: Double-check that the domain in the “From” address aligns with the domain used in the DKIM signature and SPF record. This alignment is crucial for DMARC to function correctly and prevent unauthorized senders from using your domain.
- DKIM Domains: Setting up DomainKeys Identified Mail (DKIM) correctly is essential. DKIM adds a digital signature to your emails, allowing recipients to verify that the email hasn’t been altered in transit and truly comes from your domain.
- Return-Path and Email Headers: Configuring the return-path and other email headers accurately to guarantee bounce messages are directed appropriately and that your emails pass authentication checks.
Additionally, you’ll need to establish mechanisms to verify each vendor’s configurations. This can be achieved by:
- Monitoring Authentication Status: Regularly reviewing your DMARC aggregate (RUA) reports to identify any issues with email authentication. These reports provide detailed information about the authentication status of your emails and can highlight misconfigurations or unauthorized use of your domain.
- Testing Emails: Sending test emails from the third-party sender and analyzing the header information to double-check that everything is configured correctly. This proactive approach helps catch errors before they impact your email deliverability or security.
Alternatively, you could work with an email authentication partner who can handle all of this on your behalf. A specialized partner can provide expert guidance, continuous monitoring, and comprehensive support to check that your third-party senders are correctly configured and your domain remains secure.
Partner with Valimail for better third-party sender management
Ready to take control of your email authentication and secure your domain? Contact Valimail today to learn how we can help manage third-party sender configurations and protect your email communications.
